Perceptual Impact of Video Rebuffering in a Low Bandwidth Environment

An adaptive streaming system must always mediate trade-offs among a number of performance metrics, including average bitrates, bitrate variation, the frequencies and durations of re-buffering events, and startup delay. Many video streaming providers, like Netflix, are oriented towards avoiding re-buffering (or stall) events at all costs. Given the increasing demand for video streaming in mobile devices, low bandwidth conditions and small screen viewing conditions are intertwined with the standard tradeoffs between bitrate changes and re-buffering events.

WNCG Prof. Alan C. Bovik and his students have developed a subjective testing process where different network scenarios are being simulated in order to analyze how re-buffering and bitrate changes affect each other in the low bitrate regime, under small screen viewing conditions and across different contents. The research team is also conducting a series of human studies on the quality of experience (QoE) that viewers experience when stalling / rebuffering events occur, and how the best tradeoff between rebuffering and rate control can be accomplished.